GE Energy
Position-to-flow Rate Characteristic Conversion
The parameter POSITION_CHAR_TYPE defines the characteristics between the valve
position and flow rate, and is set to one the following:
❑
1 = linear
❑
2 = equal percent (50:1)
❑
3 = equal percent (30:1)
❑
4 = quick open (reversal of equal percent 50:1)
❑
5 = Camflex Percentage
❑
255 = user-defined
Writing the value 255 allows you to define the desired characteristics by 10 line segments
for evenly divided input levels. The coordinates (0,0) and (100,100) are fixed; set the
values corresponding to OUT (Output of AO block) = 10%, 20%, 30%..., 80%, 90%. A set
value must be greater than the preceding set value; the output must increase as the input
increases.
This flow rate conversion is applied to the signal in the backward path as well.
FINAL_VALUE and Range
The parameter FINAL_VALUE contains the valve position setpoint for valve control, and
its value is always a percent value where 0% is the shut-off position as is the case for the
input signal. High and low limits for the value of FINAL_VALUE.value can be set in
FINAL_VALUE_RANGE.
Figure 56 Function Diagram of Transducer Block
FVP 110 Fieldbus Valve Positioner Manual
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